The title, 'how folk songs should be sung' is, at best, superficial and at worst, vindictive - it was not what the Critics Group was about and I would like to think the Martin Carthy had nothing to do with its choice.
The Critics Group was formed when a number of singers approached MacColl and asked him to take singing classes.
He could well have done, but instead, he chose to set up a workshop set up on the self-help principle where a number of performers and enthusiasts could meet regularly, listen to each others singing, make comments on what worked and what didn't and suggest how improvements might be made.
The first thing they did was to immerse themselves of as many types of traditional singing as were available via recordings.
MacColl provided singing and vowel exercises to develop pitch, tone, articulation, breath control.... etc, and relaxation exercised developed by Nelson Illingworth.
He introduced the idea of 'efforts', based on understanding and controlling the voice delivery in terms of weight, direction and speed - he had adapted these from Laban's theory of movement as used by dancers and actors.
That was more or less the technical side of the Group's work.
The second side of singing work was to assist a singer make a song their own using Stanislavski's 'application of the idea of IF, and emotion memory.
Far from advocating that there was a single 'right' way of "how folk songs should be sung" it was an examination of all the different ways a song might be approached and made work be each individual singer.
I have recently been listening to a recording of one of the Group singing 'The Gypsy Laddie' using five different approaches - not one way it "should" be sung, but five ways it could be approached if one way became stale though being over-sung.
It also helped develop ways of handling all the differing types of song in the repertoire, from shanties to lullabys.
Among the first work was listening to singers from all genres and attempting to imitate them; this was to try to understand your own voice, how it was produced and how to control it.
This may well have been where Charles Parker's 'Strawberry Roan' came from - Charlie never sang cowboy songs - they really weren't his 'thing'
There were other aspects to Group work, including examining specific genres of song, song writing, planning feature evenings (including poetry and prose readings) - we even did a bit of acting.
The Group was primarily set up for those who were serious about their singing and wer prepared to put in the work, but most aspects of what was done was adaptable - Pat and I helped run Singers Workshop for 15 years which was set up to assist new and less experienced sings and was run on a far more casual basis - much of what we did was taken from our Critics experiences.
I don't believe what we did was "quaint" - much of it was groundbreaking and has, to my knowledge, never been surpassed.
I know Frankie Armstrong developed what was done in the Group for her voice workshops, and Sandra Kerr used some of it in her Newcastle courses, I understand.
The incentive it gave us to 'lift the corner to see what was underneath' fed into our own work as collectors - it is a part of our lives we still value very much
Jim Carroll